| /* | |
| Flot plugin for stacking data sets, i.e. putting them on top of each | |
| other, for accumulative graphs. Note that the plugin assumes the data | |
| is sorted on x. Also note that stacking a mix of positive and negative | |
| values in most instances doesn't make sense (so it looks weird). | |
| Two or more series are stacked when their "stack" attribute is set to | |
| the same key (which can be any number or string or just "true"). To | |
| specify the default stack, you can set | |
| series: { | |
| stack: null or true or key (number/string) | |
| } | |
| or specify it for a specific series | |
| $.plot($("#placeholder"), [{ data: [ ... ], stack: true ]) | |
| The stacking order is determined by the order of the data series in | |
| the array (later series end up on top of the previous). | |
| Internally, the plugin modifies the datapoints in each series, adding | |
| an offset to the y value. For line series, extra data points are | |
| inserted through interpolation. For bar charts, the second y value is | |
| also adjusted. | |
| */ | |
| (function ($) { | |
| var options = { | |
| series: { stack: null } // or number/string | |
| }; | |
| function init(plot) { | |
| function findMatchingSeries(s, allseries) { | |
| var res = null | |
| for (var i = 0; i < allseries.length; ++i) { | |
| if (s == allseries[i]) | |
| break; | |
| if (allseries[i].stack == s.stack) | |
| res = allseries[i]; | |
| } | |
| return res; | |
| } | |
| function stackData(plot, s, datapoints) { | |
| if (s.stack == null) | |
| return; | |
| var other = findMatchingSeries(s, plot.getData()); | |
| if (!other) | |
| return; | |
| var ps = datapoints.pointsize, | |
| points = datapoints.points, | |
| otherps = other.datapoints.pointsize, | |
| otherpoints = other.datapoints.points, | |
| newpoints = [], | |
| px, py, intery, qx, qy, bottom, | |
| withlines = s.lines.show, withbars = s.bars.show, | |
| withsteps = withlines && s.lines.steps, | |
| i = 0, j = 0, l; | |
| while (true) { | |
| if (i >= points.length) | |
| break; | |
| l = newpoints.length; | |
| if (j >= otherpoints.length | |
| || otherpoints[j] == null | |
| || points[i] == null) { | |
| // degenerate cases | |
| for (m = 0; m < ps; ++m) | |
| newpoints.push(points[i + m]); | |
| i += ps; | |
| } | |
| else { | |
| // cases where we actually got two points | |
| px = points[i]; | |
| py = points[i + 1]; | |
| qx = otherpoints[j]; | |
| qy = otherpoints[j + 1]; | |
| bottom = 0; | |
| if (px == qx) { | |
| for (m = 0; m < ps; ++m) | |
| newpoints.push(points[i + m]); | |
| newpoints[l + 1] += qy; | |
| bottom = qy; | |
| i += ps; | |
| j += otherps; | |
| } | |
| else if (px > qx) { | |
| // we got past point below, might need to | |
| // insert interpolated extra point | |
| if (withlines && i > 0 && points[i - ps] != null) { | |
| intery = py + (points[i - ps + 1] - py) * (qx - px) / (points[i - ps] - px); | |
| newpoints.push(qx); | |
| newpoints.push(intery + qy) | |
| for (m = 2; m < ps; ++m) | |
| newpoints.push(points[i + m]); | |
| bottom = qy; | |
| } | |
| j += otherps; | |
| } | |
| else { | |
| for (m = 0; m < ps; ++m) | |
| newpoints.push(points[i + m]); | |
| // we might be able to interpolate a point below, | |
| // this can give us a better y | |
| if (withlines && j > 0 && otherpoints[j - ps] != null) | |
| bottom = qy + (otherpoints[j - ps + 1] - qy) * (px - qx) / (otherpoints[j - ps] - qx); | |
| newpoints[l + 1] += bottom; | |
| i += ps; | |
| } | |
| if (l != newpoints.length && withbars) | |
| newpoints[l + 2] += bottom; | |
| } | |
| // maintain the line steps invariant | |
| if (withsteps && l != newpoints.length && l > 0 | |
| && newpoints[l] != null | |
| && newpoints[l] != newpoints[l - ps] | |
| && newpoints[l + 1] != newpoints[l - ps + 1]) { | |
| for (m = 0; m < ps; ++m) | |
| newpoints[l + ps + m] = newpoints[l + m]; | |
| newpoints[l + 1] = newpoints[l - ps + 1]; | |
| } | |
| } | |
| datapoints.points = newpoints; | |
| } | |
| plot.hooks.processDatapoints.push(stackData); | |
| } | |
| $.plot.plugins.push({ | |
| init: init, | |
| options: options, | |
| name: 'stack', | |
| version: '1.0' | |
| }); | |
| })(jQuery); | |